#include <iostream>
using namespace std;

// 函数声明
double getAverage(int *arr, int size);

int main () {
    // 带有 5 个元素的整型数组
    int balance[5] = {1000, 2, 3, 17, 50};
    double avg;

    // 传递一个指向数组的指针作为参数
    avg = getAverage(balance, 5) ;

    // 输出返回值
    cout << "Average value is: " << avg << endl;

    return 0;
}

double getAverage(int *arr, int size) {
    int i, sum = 0;
    double avg;

    for (i = 0; i < size; ++i) {
        sum += arr[i];
    }

    avg = double(sum) / size;
    return avg;
}